A conventional fuel cell system may be constructed such that a fuel cell is positioned at the base of the system and offgas and moisture are discharged from the fuel cell to a gas-liquid separator that recovers the moisture from the fuel cell. In this case, it is necessary to discharge the moisture separated using the gas-liquid separator outside of the fuel cell system. However, due to the placement of the fuel cell at the base of the fuel cell system, the fuel cell system may have to use a pump, or a similar device, to move the offgas and the moisture, which includes liquid water, from the fuel cell to the gas-liquid separator. The use of a pump, or similar device, invites defects through the enlargement of the construction size and complications of fuel cell system. In addition, a pump, or similar device, to move the offgas and the moisture between components of the fuel cell system may require a power supply.